*

app/.gitignore

@@ -0,0 +1 @@
+/build

app/build.gradle.kts

@@ -0,0 +1,53 @@
+plugins {
+    alias(libs.plugins.android.application)
+}
+
+android {
+    namespace = "com.example.usbtest"
+    compileSdk = 34
+
+    defaultConfig {
+        applicationId = "com.example.usbtest"
+        minSdk = 24
+        targetSdk = 34
+        versionCode = 1
+        versionName = "1.0"
+
+        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
+        externalNativeBuild {
+            cmake {
+                cppFlags += "-std=c++17"
+            }
+        }
+    }
+
+    buildTypes {
+        release {
+            isMinifyEnabled = false
+            proguardFiles(
+                getDefaultProguardFile("proguard-android-optimize.txt"),
+                "proguard-rules.pro"
+            )
+        }
+    }
+
+    externalNativeBuild {
+        cmake {
+            path = file("src/main/cpp/CMakeLists.txt")
+            version = "3.22.1"
+        }
+    }
+    buildFeatures {
+        viewBinding = true
+    }
+}
+
+/*dependencies {
+
+    implementation(libs.appcompat)
+    implementation(libs.material)
+    implementation(libs.constraintlayout)
+    testImplementation(libs.junit)
+    androidTestImplementation(libs.ext.junit)
+    androidTestImplementation(libs.espresso.core)
+}*/

app/proguard-rules.pro

@@ -0,0 +1,21 @@
+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile

app/src/main/AndroidManifest.xml

@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+    <uses-feature android:name="android.hardware.usb.host" />
+
+    <application
+        android:allowBackup="false"
+        android:fullBackupContent="false"
+        android:label="@string/app_name"
+        android:hardwareAccelerated="true"
+        android:supportsRtl="true"
+        tools:targetApi="31"
+        android:hasCode="false">
+        <activity
+            android:name="android.app.NativeActivity"
+            android:exported="true">
+
+            <meta-data android:name="android.app.lib_name" android:value="native-activity" />
+
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+
+            <intent-filter>
+                <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />
+            </intent-filter>
+
+            <meta-data android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"
+                android:resource="@xml/device_filter" />
+        </activity>
+
+
+    </application>
+
+</manifest>

app/src/main/cpp/AppLog.h

@@ -0,0 +1,7 @@
+#pragma once
+
+#include <android/log.h>
+
+#ifndef LOGI
+#define LOGI(...) ((void)__android_log_print(ANDROID_LOG_INFO, "native-activity", __VA_ARGS__))
+#endif

app/src/main/cpp/CMakeLists.txt

@@ -0,0 +1,35 @@
+cmake_minimum_required(VERSION 3.22.1)
+
+project("native-activity")
+
+add_library(native_app_glue INTERFACE)
+
+
+
+add_library(${CMAKE_PROJECT_NAME} SHARED)
+
+target_sources(native-activity
+PRIVATE
+        native-lib.cpp
+        JniContext.h
+        AppLog.h
+        JActivityThread.h
+        JBindings.h
+        JCollection.h
+        JContext.h
+        JHashMap.h
+        JIntent.h
+        JIterator.h
+        JObject.h
+        JPackageManager.h
+        JUsbManager.h
+        ${ANDROID_NDK}/sources/android/native_app_glue/android_native_app_glue.c
+)
+
+target_include_directories(${CMAKE_PROJECT_NAME} PRIVATE
+        ${ANDROID_NDK}/sources/android/native_app_glue)
+
+target_link_libraries(${CMAKE_PROJECT_NAME}
+        android
+        log
+        native_app_glue)

app/src/main/cpp/JActivityThread.h

@@ -0,0 +1,42 @@
+#pragma once
+
+#include "JContext.h"
+
+class JActivityThreadBindings : public JBindings {
+public:
+    JActivityThreadBindings() : JBindings("android/app/ActivityThread") {
+        auto env = JniContext::getJniEnv();
+        _static_currentActivityThread = env->GetStaticMethodID(_class, "currentActivityThread", "()Landroid/app/ActivityThread;");
+        _instance_getApplication = env->GetMethodID(_class, "getApplication", "()Landroid/app/Application;");
+    }
+
+    jobject currentActivityThread() {
+        return JniContext::getJniEnv()->CallStaticObjectMethod(_class, _static_currentActivityThread);
+    }
+
+    jobject getApplication(jobject activityThreadObject) {
+        return JniContext::getJniEnv()->CallObjectMethod(activityThreadObject, _instance_getApplication);
+    }
+
+private:
+    jmethodID _static_currentActivityThread;
+    jmethodID _instance_getApplication;
+};
+
+class JActivityThread : public JObject {
+public:
+    JActivityThread(jobject instance) : JObject(instance) {
+
+    }
+    static JActivityThread currentActivityThread() {
+        return JActivityThread(localToGlobalRef(bindings().currentActivityThread()));
+    }
+    JContext getApplication() {
+        return JContext(localToGlobalRef(bindings().getApplication(_instance)));
+    }
+private:
+    static JActivityThreadBindings& bindings() {
+        static thread_local JActivityThreadBindings b;
+        return b;
+    }
+};

app/src/main/cpp/JBindings.h

@@ -0,0 +1,35 @@
+#pragma once
+
+#include "JniContext.h"
+#include <optional>
+
+class JBindings {
+protected:
+    JBindings(const char* className) {
+        JNIEnv* env = JniContext::getJniEnv();
+        _class = findClass(env, className);
+    }
+
+    std::optional<jfieldID> getStaticFieldID(const char* name, const char* signature) {
+        try{
+            auto result = JniContext::getJniEnv()->GetStaticFieldID(_class, name, signature);
+            JniContext::checkException();
+            return result;
+        }catch(...){
+            return std::nullopt;
+        }
+    }
+    //
+
+    static jclass findClass(JNIEnv* env, const char* className) {
+        auto classLocalRef = env->FindClass(className);
+        if(classLocalRef == nullptr){
+            return nullptr;
+        }
+        auto globalRef = (jclass)env->NewGlobalRef(classLocalRef);
+        env->DeleteLocalRef(classLocalRef);
+        return globalRef;
+    }
+
+    jclass _class;
+};

app/src/main/cpp/JCollection.h

@@ -0,0 +1,33 @@
+#pragma once
+
+#include "JIterator.h"
+
+class JCollectionBindings : public JBindings {
+public:
+    JCollectionBindings() : JBindings("java/util/Collection") {
+        auto env = JniContext::getJniEnv();
+        _instance_iterator = env->GetMethodID(_class, "iterator", "()Ljava/util/Iterator;");
+    }
+
+    jobject iterator(jobject _this) {
+        return JniContext::getJniEnv()->CallObjectMethod(_this, _instance_iterator);
+    }
+
+private:
+    jmethodID _instance_iterator;
+};
+
+class JCollection : public JObject {
+public:
+    JCollection(jobject instance) : JObject(instance) {
+
+    }
+    JIterator iterator() {
+        return JIterator(localToGlobalRef(bindings().iterator(_instance)));
+    }
+private:
+    static JCollectionBindings& bindings() {
+        static thread_local JCollectionBindings b;
+        return b;
+    }
+};

app/src/main/cpp/JContext.h

@@ -0,0 +1,51 @@
+#pragma once
+
+#include "JPackageManager.h"
+
+class JContextBindings : public JBindings {
+public:
+    JContextBindings() : JBindings("android/content/Context") {
+        auto env = JniContext::getJniEnv();
+        _static_field_USB_SERVICE = env->GetStaticFieldID(_class, "USB_SERVICE", "Ljava/lang/String;");
+        _instance_getPackageManager = env->GetMethodID(_class, "getPackageManager","()Landroid/content/pm/PackageManager;");
+        _instance_getSystemService = env->GetMethodID(_class, "getSystemService","(Ljava/lang/String;)Ljava/lang/Object;");
+    }
+
+    jobject get_USB_SERVICE() {
+        return JniContext::getJniEnv()->GetStaticObjectField(_class, _static_field_USB_SERVICE);
+    }
+
+    jobject getPackageManager(jobject context) {
+        return JniContext::getJniEnv()->CallObjectMethod(context, _instance_getPackageManager);
+    }
+
+    jobject getSystemService(jobject context, jobject name) {
+        return JniContext::getJniEnv()->CallObjectMethod(context, _instance_getSystemService, name);
+    }
+
+private:
+    jfieldID _static_field_USB_SERVICE;
+    jmethodID _instance_getPackageManager;
+    jmethodID _instance_getSystemService;
+};
+
+class JContext : public JObject {
+public:
+    JContext(jobject instance) : JObject(instance) {
+
+    }
+    static jobject get_USB_SERVICE() {
+        return localToGlobalRef(bindings().get_USB_SERVICE());
+    }
+    JPackageManager getPackageManager() {
+        return JPackageManager(localToGlobalRef(bindings().getPackageManager(_instance)));
+    }
+    jobject getSystemService(jobject usbService) {
+        return localToGlobalRef(bindings().getSystemService(_instance, usbService));
+    }
+private:
+    static JContextBindings& bindings() {
+        static thread_local JContextBindings b;
+        return b;
+    }
+};

app/src/main/cpp/JHashMap.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include "JCollection.h"
+
+class JHashMapBindings : public JBindings {
+public:
+    JHashMapBindings() : JBindings("java/util/HashMap") {
+        auto env = JniContext::getJniEnv();
+        _instance_values = env->GetMethodID(_class, "values", "()Ljava/util/Collection;");
+        _instance_keySet = env->GetMethodID(_class, "keySet", "()Ljava/util/Set;");
+    }
+    jobject values(jobject _this) {
+        return JniContext::getJniEnv()->CallObjectMethod(_this, _instance_values);
+    }
+    jobject keySet(jobject _this) {
+        return JniContext::getJniEnv()->CallObjectMethod(_this, _instance_keySet);
+    }
+private:
+    jmethodID _instance_values;
+    jmethodID _instance_keySet;
+};
+
+class JHashMap : public JObject {
+public:
+    JHashMap(jobject instance) : JObject(instance) {
+
+    }
+    JCollection values() { //Collection<UsbDevice>
+        return JCollection(localToGlobalRef(bindings().values(_instance)));
+    }
+
+    JCollection keySet() { //Set<String>
+        return JCollection(localToGlobalRef(bindings().keySet(_instance)));
+    }
+private:
+    static JHashMapBindings& bindings() {
+        static thread_local JHashMapBindings b;
+        return b;
+    }
+};

app/src/main/cpp/JIntent.h

@@ -0,0 +1,21 @@
+#pragma once
+
+#include "JBindings.h"
+
+class JIntentBindings : public JBindings {
+public:
+    JIntentBindings() : JBindings("android/content/Intent") {
+        auto env = JniContext::getJniEnv();
+        _instance_init = env->GetMethodID(_class, "<init>", "(Ljava/lang/String;)V");
+    }
+
+    jobject construct(jobject permissionAction) {
+        return JniContext::getJniEnv()->NewObject(_class, _instance_init, permissionAction);
+    }
+
+private:
+    jmethodID _instance_init;
+};
+
+
+

app/src/main/cpp/JIterator.h

@@ -0,0 +1,41 @@
+#pragma once
+
+#include "JObject.h"
+#include "JBindings.h"
+
+class JIteratorBindings : public JBindings {
+public:
+    JIteratorBindings() : JBindings("java/util/Iterator") {
+        auto env = JniContext::getJniEnv();
+        _instance_hasNext = env->GetMethodID(_class, "hasNext", "()Z");
+        _instance_next = env->GetMethodID(_class, "next", "()Ljava/lang/Object;");
+    }
+
+    jboolean hasNext(jobject _this) {
+        return JniContext::getJniEnv()->CallBooleanMethod(_this, _instance_hasNext);
+    }
+    jobject next(jobject _this) {
+        return JniContext::getJniEnv()->CallObjectMethod(_this, _instance_next);
+    }
+
+private:
+    jmethodID _instance_hasNext;
+    jmethodID _instance_next;
+};
+class JIterator : public JObject {
+public:
+    JIterator(jobject instance) : JObject(instance) {
+
+    }
+    jboolean hasNext() {
+        return bindings().hasNext(_instance);
+    }
+    jobject next() {
+        return localToGlobalRef(bindings().next(_instance));
+    }
+private:
+    static JIteratorBindings& bindings() {
+        static thread_local JIteratorBindings b;
+        return b;
+    }
+};

app/src/main/cpp/JObject.h

@@ -0,0 +1,32 @@
+#pragma once
+
+#include "JniContext.h"
+
+class JObject {
+public:
+    JObject(jobject instance) {
+        _instance = instance;
+    }
+    JObject(const JObject&) = delete;
+    //JObject(const JObject&& src) {
+
+    //}
+    jobject toNativeObject() {
+        return _instance;
+    }
+    ~JObject() {
+        release();
+    }
+protected:
+    static jobject localToGlobalRef(jobject obj){
+        auto result = JniContext::getJniEnv()->NewGlobalRef(obj);
+        JniContext::getJniEnv()->DeleteLocalRef(obj);
+        return result;
+    }
+    jobject _instance = nullptr;
+    void release() {
+        if(_instance != nullptr){
+            JniContext::getJniEnv()->DeleteGlobalRef(_instance);
+        }
+    }
+};

app/src/main/cpp/JPackageManager.h

@@ -0,0 +1,43 @@
+#pragma once
+
+#include "JBindings.h"
+#include "JObject.h"
+
+class JPackageManagerBindings : public JBindings {
+public:
+    JPackageManagerBindings() : JBindings("android/content/pm/PackageManager") {
+        auto env = JniContext::getJniEnv();
+        _static_field_FEATURE_USB_HOST = env->GetStaticFieldID(_class, "FEATURE_USB_HOST", "Ljava/lang/String;");
+        _instance_hasSystemFeature = env->GetMethodID(_class, "hasSystemFeature","(Ljava/lang/String;)Z");
+    }
+
+    jobject get_FEATURE_USB_HOST() {
+        return JniContext::getJniEnv()->GetStaticObjectField(_class, _static_field_FEATURE_USB_HOST);
+    }
+
+    jboolean hasSystemFeature(jobject packageManager, jobject name) {
+        return JniContext::getJniEnv()->CallBooleanMethod(packageManager, _instance_hasSystemFeature, name);
+    }
+
+private:
+    jfieldID _static_field_FEATURE_USB_HOST;
+    jmethodID _instance_hasSystemFeature;
+};
+
+class JPackageManager : public JObject {
+public:
+    JPackageManager(jobject instance) : JObject(instance) {
+
+    }
+    static jobject get_FEATURE_USB_HOST() {
+        return localToGlobalRef(bindings().get_FEATURE_USB_HOST());
+    }
+    jboolean hasSystemFeature(jobject name) {
+        return bindings().hasSystemFeature(_instance, name);
+    }
+private:
+    static JPackageManagerBindings& bindings() {
+        static thread_local JPackageManagerBindings b;
+        return b;
+    }
+};

app/src/main/cpp/JPendingIntent.h

@@ -0,0 +1,91 @@
+#pragma once
+
+#include "JBindings.h"
+#include "JObject.h"
+#include "JContext.h"
+#include "JIntent.h"
+#include <optional>
+
+class JPendingIntentBindings : public JBindings {
+public:
+    JPendingIntentBindings() : JBindings("android/app/PendingIntent") {
+        auto env = JniContext::getJniEnv();
+        _static_getBroadcast = env->GetStaticMethodID(_class, "getBroadcast", "(Landroid/content/Context;ILandroid/content/Intent;I)Landroid/app/PendingIntent;");
+
+        _static_field_FLAG_ALLOW_UNSAFE_IMPLICIT_INTENT = getStaticFieldID("FLAG_ALLOW_UNSAFE_IMPLICIT_INTENT", "I");
+        _static_field_FLAG_CANCEL_CURRENT = getStaticFieldID("FLAG_CANCEL_CURRENT", "I");
+        _static_field_FLAG_IMMUTABLE = getStaticFieldID("FLAG_IMMUTABLE", "I");
+        _static_field_FLAG_MUTABLE = getStaticFieldID("FLAG_MUTABLE", "I");
+        _static_field_FLAG_NO_CREATE = getStaticFieldID("FLAG_NO_CREATE", "I");
+        _static_field_FLAG_ONE_SHOT = getStaticFieldID("FLAG_ONE_SHOT", "I");
+        _static_field_FLAG_UPDATE_CURRENT = getStaticFieldID("FLAG_UPDATE_CURRENT", "I");
+    }
+
+    jobject getBroadcast(jobject context, jint requestCode, jobject intent, jint flags) { //getBroadcast(Context, int, Intent, int)
+        jobject result = JniContext::getJniEnv()->CallStaticObjectMethod(_class, _static_getBroadcast, context, requestCode, intent, flags);
+        JniContext::checkException();
+        return result;
+    }
+
+    jint get_FLAG_ALLOW_UNSAFE_IMPLICIT_INTENT() {
+        jint result = JniContext::getJniEnv()->GetStaticIntField(_class, _static_field_FLAG_ALLOW_UNSAFE_IMPLICIT_INTENT.value());
+        return result;
+    }
+    jint get_FLAG_CANCEL_CURRENT() {
+        jint result = JniContext::getJniEnv()->GetStaticIntField(_class, _static_field_FLAG_CANCEL_CURRENT.value());
+        return result;
+    }
+    jint get_FLAG_IMMUTABLE() {
+        jint result = JniContext::getJniEnv()->GetStaticIntField(_class, _static_field_FLAG_IMMUTABLE.value());
+        return result;
+    }
+    jint get_FLAG_MUTABLE() {
+        jint result = JniContext::getJniEnv()->GetStaticIntField(_class, _static_field_FLAG_MUTABLE.value());
+        return result;
+    }
+    jint get_FLAG_NO_CREATE() {
+        jint result = JniContext::getJniEnv()->GetStaticIntField(_class, _static_field_FLAG_NO_CREATE.value());
+        return result;
+    }
+    jint get_FLAG_ONE_SHOT() {
+        jint result = JniContext::getJniEnv()->GetStaticIntField(_class, _static_field_FLAG_ONE_SHOT.value());
+        return result;
+    }
+    jint get_FLAG_UPDATE_CURRENT() {
+        jint result = JniContext::getJniEnv()->GetStaticIntField(_class, _static_field_FLAG_UPDATE_CURRENT.value());
+        return result;
+    }
+private:
+    jmethodID _static_getBroadcast;
+
+    std::optional<jfieldID> _static_field_FLAG_ALLOW_UNSAFE_IMPLICIT_INTENT;
+    std::optional<jfieldID> _static_field_FLAG_CANCEL_CURRENT;
+    std::optional<jfieldID> _static_field_FLAG_IMMUTABLE;
+    std::optional<jfieldID> _static_field_FLAG_MUTABLE;
+    std::optional<jfieldID> _static_field_FLAG_NO_CREATE;
+    std::optional<jfieldID> _static_field_FLAG_ONE_SHOT;
+    std::optional<jfieldID> _static_field_FLAG_UPDATE_CURRENT;
+};
+
+class JPendingIntent : public JObject {
+public:
+    JPendingIntent(jobject instance) : JObject(instance) {
+
+    }
+    static JPendingIntent getBroadcast(JContext& context, jint requestCode, jobject intent, jint flags) {
+        return JPendingIntent(localToGlobalRef(bindings().getBroadcast(context.toNativeObject(), requestCode, intent, flags)));
+    }
+
+    static jint get_FLAG_ALLOW_UNSAFE_IMPLICIT_INTENT() { return bindings().get_FLAG_ALLOW_UNSAFE_IMPLICIT_INTENT(); }
+    static jint get_FLAG_CANCEL_CURRENT() { return bindings().get_FLAG_CANCEL_CURRENT(); }
+    static jint get_FLAG_IMMUTABLE() { return bindings().get_FLAG_IMMUTABLE(); }
+    static jint get_FLAG_MUTABLE() { return bindings().get_FLAG_MUTABLE(); }
+    static jint get_FLAG_NO_CREATE() { return bindings().get_FLAG_NO_CREATE(); }
+    static jint get_FLAG_ONE_SHOT() { return bindings().get_FLAG_ONE_SHOT(); }
+    static jint get_FLAG_UPDATE_CURRENT() { return bindings().get_FLAG_UPDATE_CURRENT(); }
+private:
+    static JPendingIntentBindings& bindings() {
+        static thread_local JPendingIntentBindings b;
+        return b;
+    }
+};

app/src/main/cpp/JUsbManager.h

@@ -0,0 +1,57 @@
+#pragma once
+
+#include "JHashMap.h"
+#include "JPendingIntent.h"
+
+class JUsbManagerBindings : public JBindings {
+public:
+    JUsbManagerBindings() : JBindings("android/hardware/usb/UsbManager") {
+        auto env = JniContext::getJniEnv();
+        _instance_getDeviceList = env->GetMethodID(_class, "getDeviceList", "()Ljava/util/HashMap;");
+        _instance_hasPermission = env->GetMethodID(_class, "hasPermission", "(Landroid/hardware/usb/UsbDevice;)Z");
+        _instance_openDevice = env->GetMethodID(_class, "openDevice", "(Landroid/hardware/usb/UsbDevice;)Landroid/hardware/usb/UsbDeviceConnection;");
+        _instance_requestPermission = env->GetMethodID(_class, "requestPermission", "(Landroid/hardware/usb/UsbDevice;Landroid/app/PendingIntent;)V");
+    }
+
+    jobject getDeviceList(jobject _this) { //HashMap<String, UsbDevice>
+        return JniContext::getJniEnv()->CallObjectMethod(_this, _instance_getDeviceList);
+    }
+    jboolean hasPermission(jobject _this, jobject device) {
+        return JniContext::getJniEnv()->CallBooleanMethod(_this, _instance_hasPermission, device);
+    }
+    jobject openDevice(jobject _this, jobject device) { //UsbDeviceConnection connection = usbManager.openDevice(device);
+        return JniContext::getJniEnv()->CallObjectMethod(_this, _instance_openDevice, device);
+    }
+    void requestPermission(jobject _this, jobject device, jobject permissionIntent) {
+        return JniContext::getJniEnv()->CallVoidMethod(_this, _instance_requestPermission, device, permissionIntent);
+    }
+private:
+    jmethodID _instance_getDeviceList;
+    jmethodID _instance_hasPermission;
+    jmethodID _instance_openDevice;
+    jmethodID _instance_requestPermission;
+};
+
+class JUsbManager : public JObject {
+public:
+    JUsbManager(jobject instance) : JObject(instance) {
+
+    }
+    JHashMap getDeviceList() {
+        return JHashMap(localToGlobalRef(bindings().getDeviceList(_instance)));
+    }
+    jboolean hasPermission(jobject device) {
+        return bindings().hasPermission(_instance, device);
+    }
+    jobject openDevice(jobject device) {
+        return localToGlobalRef(bindings().openDevice(_instance, device));
+    }
+    void requestPermission(jobject device, JPendingIntent& permissionIntent) {
+        bindings().requestPermission(_instance, device, permissionIntent.toNativeObject());
+    }
+private:
+    static JUsbManagerBindings& bindings() {
+        static thread_local JUsbManagerBindings b;
+        return b;
+    }
+};

app/src/main/cpp/JniContext.h

@@ -0,0 +1,70 @@
+#pragma once
+#include <jni.h>
+#include "AppLog.h"
+
+class JniContext {
+public:
+    static void setJavaVM(JavaVM* vm){
+        auto& i = instance();
+        i._vm = vm;
+    }
+
+    static JavaVM* getJavaVM(){
+        auto& i = instance();
+        return i._vm;
+    }
+
+    static void checkException() {
+        auto env = getJniEnv();
+        if(env->ExceptionCheck()){
+            env->ExceptionDescribe(); // print the stack trace
+            env->ExceptionClear();
+            throw std::runtime_error("");
+        }
+    }
+
+
+    static JNIEnv* getJniEnv() {
+        auto& i = instance();
+        if(i._vm == nullptr){
+            return nullptr;
+        }
+
+        if(i._env == nullptr){
+            LOGI("getJniEnv: query Jni Env for thread");
+            int status = i._vm->GetEnv( (void**)&i._env, JNI_VERSION_1_1);
+            if (status == JNI_EDETACHED) {
+                LOGI("getJniEnv: thread Detached! Attaching...");
+                JavaVMAttachArgs thr_args = {
+                        .version = JNI_VERSION_1_6,
+                        .name = NULL,
+                        .group = NULL
+                };
+                status = i._vm->AttachCurrentThread(&i._env, &thr_args);
+                if(status != JNI_OK){
+                    LOGI("getJniEnv: thread failed to attach");
+                    return nullptr;
+                }
+                LOGI("getJniEnv: thread attached successfully");
+            }else{
+                LOGI("getJniEnv: Something went wrong!!!!!");
+            }
+        }
+
+        return i._env;
+    }
+    ~JniContext() {
+        if(_env != nullptr){
+            LOGI("getJniEnv: detaching current thread...");
+            _vm->DetachCurrentThread();
+        }
+    }
+private:
+    JniContext() = default;
+    static JniContext& instance() {
+        static thread_local JniContext context;
+        return context;
+    }
+    JavaVM* _vm = nullptr;
+    JNIEnv* _env = nullptr;
+};

app/src/main/cpp/native-lib.cpp

@@ -0,0 +1,79 @@
+#include <jni.h>
+#include <string>
+#include <android_native_app_glue.h>
+#include "AppLog.h"
+#include "JniContext.h"
+#include <memory>
+
+#include "JUsbManager.h"
+#include "JIntent.h"
+#include "JActivityThread.h"
+#include "JPendingIntent.h"
+
+#include <thread>
+#include <chrono>
+
+void requestPermission(JContext& context, JUsbManager& usbManager, jobject usbDevice, jobject permissionAction){
+    JIntentBindings b;
+    jobject intent = b.construct(permissionAction);
+    jobject intentRef = JniContext::getJniEnv()->NewGlobalRef(intent);
+    auto permissionIntent = JPendingIntent::getBroadcast(context, 0, intentRef, JPendingIntent::get_FLAG_IMMUTABLE());
+    usbManager.requestPermission(usbDevice, permissionIntent);
+    JniContext::getJniEnv()->DeleteGlobalRef(intentRef);
+}
+
+void android_main(android_app* state) {
+    JniContext::setJavaVM(state->activity->vm);
+
+    auto activityThread = JActivityThread::currentActivityThread();
+    auto application = activityThread.getApplication();
+    auto usbServiceName = application.get_USB_SERVICE();
+    JUsbManager usbManager(application.getSystemService(usbServiceName));
+
+
+    auto packageManager = application.getPackageManager();
+
+    auto featureUsbHost = packageManager.get_FEATURE_USB_HOST();
+    auto hasUsbHost = packageManager.hasSystemFeature(featureUsbHost);
+
+
+
+    jint flagImmutable = JPendingIntent::get_FLAG_IMMUTABLE();
+    LOGI("!!!!Flag immutable: %i", flagImmutable);
+
+
+    jobject permissionActionNameLocal = JniContext::getJniEnv()->NewStringUTF("android.app.USB_PERMISSION");
+    jobject permissionActionName = JniContext::getJniEnv()->NewGlobalRef(permissionActionNameLocal);
+    //JniContext::getJniEnv()->DeleteLocalRef(permissionActionNameLocal);
+
+
+    while(true){
+        LOGI("Enumerating USB devices...");
+        auto usbDeviceHashMap = usbManager.getDeviceList(); //HashMap<String, UsbDevice>
+        auto usbDeviceList = usbDeviceHashMap.values();
+        auto usbDeviceIterator = usbDeviceList.iterator();
+
+        int deviceId = 0;
+
+        while(usbDeviceIterator.hasNext()){
+            auto device = usbDeviceIterator.next();
+            auto hasPermission = usbManager.hasPermission(device);
+            LOGI("Found USB device: %i, has permission: %s", deviceId, (hasPermission ? "yes" : "no"));
+
+            if(!hasPermission){
+                LOGI("Requesting permission for device  %i", deviceId);
+                requestPermission(application, usbManager, device, permissionActionName);
+            }
+            JniContext::getJniEnv()->DeleteGlobalRef(device);
+
+            deviceId++;
+        }
+        std::this_thread::sleep_for(std::chrono::milliseconds(1000));
+    }
+
+
+
+
+
+    LOGI("App exiting...");
+}

app/src/main/res/drawable/ic_launcher_background.xml

@@ -0,0 +1,170 @@
+<?xml version="1.0" encoding="utf-8"?>
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path
+        android:fillColor="#3DDC84"
+        android:pathData="M0,0h108v108h-108z" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M9,0L9,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,0L19,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,0L29,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,0L39,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,0L49,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,0L59,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,0L69,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,0L79,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M89,0L89,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M99,0L99,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,9L108,9"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,19L108,19"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,29L108,29"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,39L108,39"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,49L108,49"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,59L108,59"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,69L108,69"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,79L108,79"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,89L108,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,99L108,99"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,29L89,29"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,39L89,39"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,49L89,49"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,59L89,59"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,69L89,69"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,79L89,79"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,19L29,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,19L39,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,19L49,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,19L59,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,19L69,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,19L79,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+</vector>

app/src/main/res/drawable/ic_launcher_foreground.xml

@@ -0,0 +1,30 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:aapt="http://schemas.android.com/aapt"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path android:pathData="M31,63.928c0,0 6.4,-11 12.1,-13.1c7.2,-2.6 26,-1.4 26,-1.4l38.1,38.1L107,108.928l-32,-1L31,63.928z">
+        <aapt:attr name="android:fillColor">
+            <gradient
+                android:endX="85.84757"
+                android:endY="92.4963"
+                android:startX="42.9492"
+                android:startY="49.59793"
+                android:type="linear">
+                <item
+                    android:color="#44000000"
+                    android:offset="0.0" />
+                <item
+                    android:color="#00000000"
+                    android:offset="1.0" />
+            </gradient>
+        </aapt:attr>
+    </path>
+    <path
+        android:fillColor="#FFFFFF"
+        android:fillType="nonZero"
+        android:pathData="M65.3,45.828l3.8,-6.6c0.2,-0.4 0.1,-0.9 -0.3,-1.1c-0.4,-0.2 -0.9,-0.1 -1.1,0.3l-3.9,6.7c-6.3,-2.8 -13.4,-2.8 -19.7,0l-3.9,-6.7c-0.2,-0.4 -0.7,-0.5 -1.1,-0.3C38.8,38.328 38.7,38.828 38.9,39.228l3.8,6.6C36.2,49.428 31.7,56.028 31,63.928h46C76.3,56.028 71.8,49.428 65.3,45.828zM43.4,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2c-0.3,-0.7 -0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C45.3,56.528 44.5,57.328 43.4,57.328L43.4,57.328zM64.6,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2s-0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C66.5,56.528 65.6,57.328 64.6,57.328L64.6,57.328z"
+        android:strokeWidth="1"
+        android:strokeColor="#00000000" />
+</vector>

app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background" />
+    <foreground android:drawable="@drawable/ic_launcher_foreground" />
+    <monochrome android:drawable="@drawable/ic_launcher_foreground" />
+</adaptive-icon>

app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background" />
+    <foreground android:drawable="@drawable/ic_launcher_foreground" />
+    <monochrome android:drawable="@drawable/ic_launcher_foreground" />
+</adaptive-icon>

app/src/main/res/values/colors.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="purple_200">#FFBB86FC</color>
+    <color name="purple_500">#FF6200EE</color>
+    <color name="purple_700">#FF3700B3</color>
+    <color name="teal_200">#FF03DAC5</color>
+    <color name="teal_700">#FF018786</color>
+    <color name="black">#FF000000</color>
+    <color name="white">#FFFFFFFF</color>
+</resources>

app/src/main/res/values/strings.xml

@@ -0,0 +1,3 @@
+<resources>
+    <string name="app_name">UsbTest</string>
+</resources>

app/src/main/res/xml/backup_rules.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample backup rules file; uncomment and customize as necessary.
+   See https://developer.android.com/guide/topics/data/autobackup
+   for details.
+   Note: This file is ignored for devices older that API 31
+   See https://developer.android.com/about/versions/12/backup-restore
+-->
+<full-backup-content>
+    <!--
+   <include domain="sharedpref" path="."/>
+   <exclude domain="sharedpref" path="device.xml"/>
+-->
+</full-backup-content>

app/src/main/res/xml/data_extraction_rules.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample data extraction rules file; uncomment and customize as necessary.
+   See https://developer.android.com/about/versions/12/backup-restore#xml-changes
+   for details.
+-->
+<data-extraction-rules>
+    <cloud-backup>
+        <!-- TODO: Use <include> and <exclude> to control what is backed up.
+        <include .../>
+        <exclude .../>
+        -->
+    </cloud-backup>
+    <!--
+    <device-transfer>
+        <include .../>
+        <exclude .../>
+    </device-transfer>
+    -->
+</data-extraction-rules>

app/src/main/res/xml/device_filter.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+	<usb-device vendor-id="12855"/>
+</resources>